This award will support the participation of U.S. scientists in a seminar on the "Mechanisms Regulating Initiation and Conduction of the Cardiac Impulse," organized by Professor Melvyn Lieberman of Duke University and Dr. David Gadsby of Rockefeller University, together with Professor Akinori Noma of Kyushu University, Japan. United States and Japanese participants will meet at the National Institute for Physiological Sciences in Okazaki, Japan during April 1988. The seminar will focus on recent developments in electrophysiology and biophysics which have advanced studies on understanding how the heart functions. The major areas that will be examined are ion channel current, ion transport systems, mechanisms of extracellular and intracellular regulatory signals, and intercellular communication. Research in cardiac electrophysiology has progressed considerably because of contributions from laboratories both in the United States and Japan. Cooperative efforts between investigators in both countries have led to the development of several technological and intellectual breakthroughs. This seminar, by providing a forum for the exchange of current research results and ideas, will promote continued cooperation and progress in the field.